Study · Toxicology · 2012

Sunset yellow and tartrazine activate human oestrogen receptor in lab tests

What it found

In lab tests on human breast cancer cells, the food colourings sunset yellow and tartrazine switched on the oestrogen receptor.

Sunset yellow was about 50 times weaker than the natural hormone oestradiol.

What they found

Animal and lab studies

Sunset yellow activates ER

In the MCF-7 cell test, sunset yellow activated the human oestrogen receptor alpha. Its EC50 was 220 nM.

Tartrazine activates ER

Tartrazine also activated the oestrogen receptor alpha in the same test, with an EC50 of 160 nM.

Potency compared to oestradiol

Both colourings were about 50 times less effective than the natural hormone oestradiol at activating the receptor. They were more potent than parabens.

Blocked by ER antagonist

The ER antagonist ICI182780 blocked the receptor activation by sunset yellow and tartrazine. This confirms they act through the oestrogen receptor.

Other findings

Possible exposure levels

The authors calculated that at high dietary intakes, blood levels of these colourings could exceed the concentrations needed to activate the receptor in the lab test.

What the authors conclude

“Our data suggest that compounds like tartrazine and sunset yellow – whilst not the cause - may be a component contributor to the development of cholestasis and which in combination with other factors, could pre-dispose to the development of PBC.”
Axon A, May FE, Gaughan LE, Williams FM, Blain PG, Wright MC, 2012

Also in their conclusions

  • They say that compounds like tartrazine and sunset yellow may be a component contributor to the development of cholestasis, which in combination with other factors could pre-dispose to primary biliary cirrhosis.
  • They note that these colourings are not likely to be appreciably absorbed via the gut or skin, but that gut and skin permeability can be affected by other agents.
  • They suggest that in high exposed individuals, intake may be sufficient for these chemicals to have an oestrogenic effect.

How it was done

The authors wanted to find out whether chemicals linked to a liver disease called primary biliary cirrhosis could act like the hormone oestrogen. They built a new test to screen for such chemicals.

They made a test using human breast cancer cells (MCF-7) that lights up when the oestrogen receptor is activated. They then screened a range of chemicals, including food and cosmetic additives, for their ability to activate the receptor.

What it can’t tell you

  • These are lab tests on human breast cancer cells. They can't show what happens in people.
  • The study did not measure whether sunset yellow or tartrazine actually cause liver disease or cholestasis in humans.
  • The authors did not test whether the colourings affect the oestrogen receptor beta, only alpha.

The paper

Title
Tartrazine and sunset yellow are xenoestrogens in a new screening assay to identify modulators of human oestrogen receptor transcriptional activity
Type
Study
Evidence
Animals and lab studies
Summarised from
Full text
Cite
Axon A, May FE, Gaughan LE, Williams FM, Blain PG, Wright MC (2012). Tartrazine and sunset yellow are xenoestrogens in a new screening assay to identify modulators of human oestrogen receptor transcriptional activity. Toxicology. doi:10.1016/j.tox.2012.04.014Free full textPubMed 22562034DOI

Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error